1.4 Tools & Techniques Microscopes– tools that extend human vision by making enlarged images of objects Magnification – power to increase the size of an object Resolution – power to show details clearly 1

1.4 Tools & Techniques 2 Types of Microscopes Light microscope– shines a light through a specimen Has 4 lenses Objective lenses 4x - scanning 10x – low power 40x – high power Ocular lens (also called the eyepiece) = 10x 2

1.4 Tools & Techniques Total magnification = objective lens X ocular lens (10x) What is my total magnification if I am on high power?   Compound Light microscope Objects can be LIVING Lower cost than other microscopes Commonly used in science classes Maximum magnification is 2,000x 3

1.4 Tools & Techniques 2. Electron microscope– a beam of electrons produces an enlarged image of the specimen Scanning Electron Microscope (SEM) – passes a beam of electrons over the specimen to produce a 3-D image (max magnification = 100,000 times) 4

1.4 Tools & Techniques Transmission Electron Microscope (TEM) – transmits a beam of electrons through a thin slice of the specimen (max magnification = 200,000 times) Better magnification $$$ Specimens have to be dead 5

1.4 Tools & Techniques Basic Units of Measurement Base Quantity Name Abbreviation Length meter m Mass kilogram kg Time second s Temperature kelvin k 6